Bandwidth and cost. There are a limited number of frequencies made available for wireless remotes and a much larger number of remote controller consumer devices. It's a lot easier to share frequencies if the range is limited. If my remote's power (and thus range) is so limited that I can't possibly change channels on my neighbor's identical set, our remotes can be interchangeable and extremely cheap. If they had longer range, they'd need a bluetooth-like pairing scheme and spread-spectrum channel allocation, making them more costly and less "user friendly." The cheap, range limited remotes just work.

I built something with a similar function, but set to a timer to let our dog out at a specific time. I created a vessel using PVC pipe and end caps, plus a tire valve. I charged it with compressed air as my energy source. I wired a sprinkler solenoid to release the air, which acted on an air cylinder that was the deadbolt for the kennel. A bungee cord swung the door open so he could get out.

It wasn't about being lazy as someone else mentioned. We kept the dog in a kennel in the garage after we left for work, so he wouldn't disturb the neighbors at an early hour. After getting out of the kennel, he had access to the yard.

The main reason I am not inpressed is the over use of China products. I would like to see a better use of American made products. We as a country need to support our American manufacturers and workers.

Also, the gadget is a little too simple with no real consumer value. I still have to get up and go outside to put the animal back in the cage. People are becoming too lazy and over dependant on technology.

Actually I had the same problem with the privacy fence gate at the side of my house. After seeing what some companies offered and charged, I about passed out. The solution was simple and required no batteries! I took a few i/4' Dia eye bolts and a long length of 1/8 Dia polyester cord. One of the eye bols I used for the locking bolt and the others were used as stand-offs/guides for the cord. I dressed the end of the cord off with a 1 1/2' Dia wooden ball with a 3/16 Dia. hole drilled through it and tied a stopper knot at the end. Pulling the ball pulls the eye bolt out of the gate padlocking plates. The great thing about this design is, all components were made right here in the USA.

If I had to go through a wall I would of inserted a tube through a wall opening, flanged and caulked both ends, and used a fancy wine bottle cork that fitted the inside opening and fitted this to end the cord!

Now I could add one of those flashing red lights they sell for bicycles if some of you electro guys need to have something that glows to look at!

I know lots of people in the semi-rural area where I live who'd love a device like this for their chicken coops and horse pens, especially in the winter. I have to agree with Doug, though, it seems a bit hard to believe something doesn't exist out there to do this. The other option for the pooches is the good old electric fence and doggie door. That's our set up and my dogs go in and out at their leisure.

Again, we have a gadget that goes through walls. And again, it makes me wonder why our common remotes are so weak. If our gadget freaks can make remotes that go through walls, why isn't that feature more common with consumer electronics?

Seems pretty hard to believe something like this isn't already available. The video demonstration would have been more effective if done at a distance showing the ability to go through walls and other obstacles.

A few weeks ago, Ford Motor Co. quietly announced that it was rolling out a new wrinkle to the powerful safety feature called stability control, adding even more lifesaving potential to a technology that has already been very successful.

It won't be too much longer and hardware design, as we used to know it, will be remembered alongside the slide rule and the Karnaugh map. You will need to move beyond those familiar bits and bytes into the new world of software centric design.

People who want to take advantage of solar energy in their homes no longer need to install a bolt-on solar-panel system atop their houses -- they can integrate solar-energy-harvesting shingles directing into an existing or new roof instead.

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